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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4349 | Serge | 1 | /* |
| 2 | * Real Audio 1.0 (14.4K) |
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| 3 | * |
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| 4 | * Copyright (c) 2008 Vitor Sessak |
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| 5 | * Copyright (c) 2003 Nick Kurshev |
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| 6 | * Based on public domain decoder at http://www.honeypot.net/audio |
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| 7 | * |
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| 8 | * This file is part of FFmpeg. |
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| 9 | * |
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| 10 | * FFmpeg is free software; you can redistribute it and/or |
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| 11 | * modify it under the terms of the GNU Lesser General Public |
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| 12 | * License as published by the Free Software Foundation; either |
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| 13 | * version 2.1 of the License, or (at your option) any later version. |
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| 14 | * |
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| 15 | * FFmpeg is distributed in the hope that it will be useful, |
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| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 18 | * Lesser General Public License for more details. |
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| 19 | * |
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| 20 | * You should have received a copy of the GNU Lesser General Public |
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| 21 | * License along with FFmpeg; if not, write to the Free Software |
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| 22 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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| 23 | */ |
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| 24 | |||
| 25 | #include "libavutil/channel_layout.h" |
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| 26 | #include "avcodec.h" |
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| 27 | #include "get_bits.h" |
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| 28 | #include "internal.h" |
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| 29 | #include "ra144.h" |
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| 30 | |||
| 31 | |||
| 32 | static av_cold int ra144_decode_init(AVCodecContext * avctx) |
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| 33 | { |
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| 34 | RA144Context *ractx = avctx->priv_data; |
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| 35 | |||
| 36 | ractx->avctx = avctx; |
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| 37 | |||
| 38 | ractx->lpc_coef[0] = ractx->lpc_tables[0]; |
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| 39 | ractx->lpc_coef[1] = ractx->lpc_tables[1]; |
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| 40 | |||
| 41 | avctx->channels = 1; |
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| 42 | avctx->channel_layout = AV_CH_LAYOUT_MONO; |
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| 43 | avctx->sample_fmt = AV_SAMPLE_FMT_S16; |
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| 44 | |||
| 45 | return 0; |
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| 46 | } |
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| 47 | |||
| 48 | static void do_output_subblock(RA144Context *ractx, const int16_t *lpc_coefs, |
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| 49 | int gval, GetBitContext *gb) |
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| 50 | { |
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| 51 | int cba_idx = get_bits(gb, 7); // index of the adaptive CB, 0 if none |
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| 52 | int gain = get_bits(gb, 8); |
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| 53 | int cb1_idx = get_bits(gb, 7); |
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| 54 | int cb2_idx = get_bits(gb, 7); |
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| 55 | |||
| 56 | ff_subblock_synthesis(ractx, lpc_coefs, cba_idx, cb1_idx, cb2_idx, gval, |
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| 57 | gain); |
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| 58 | } |
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| 59 | |||
| 60 | /** Uncompress one block (20 bytes -> 160*2 bytes). */ |
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| 61 | static int ra144_decode_frame(AVCodecContext * avctx, void *data, |
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| 62 | int *got_frame_ptr, AVPacket *avpkt) |
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| 63 | { |
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| 64 | AVFrame *frame = data; |
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| 65 | const uint8_t *buf = avpkt->data; |
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| 66 | int buf_size = avpkt->size; |
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| 67 | static const uint8_t sizes[LPC_ORDER] = {6, 5, 5, 4, 4, 3, 3, 3, 3, 2}; |
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| 68 | unsigned int refl_rms[NBLOCKS]; // RMS of the reflection coefficients |
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| 69 | int16_t block_coefs[NBLOCKS][LPC_ORDER]; // LPC coefficients of each sub-block |
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| 70 | unsigned int lpc_refl[LPC_ORDER]; // LPC reflection coefficients of the frame |
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| 71 | int i, j; |
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| 72 | int ret; |
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| 73 | int16_t *samples; |
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| 74 | unsigned int energy; |
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| 75 | |||
| 76 | RA144Context *ractx = avctx->priv_data; |
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| 77 | GetBitContext gb; |
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| 78 | |||
| 79 | if (buf_size < FRAME_SIZE) { |
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| 80 | av_log(avctx, AV_LOG_ERROR, |
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| 81 | "Frame too small (%d bytes). Truncated file?\n", buf_size); |
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| 82 | *got_frame_ptr = 0; |
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| 83 | return AVERROR_INVALIDDATA; |
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| 84 | } |
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| 85 | |||
| 86 | /* get output buffer */ |
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| 87 | frame->nb_samples = NBLOCKS * BLOCKSIZE; |
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| 88 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
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| 89 | return ret; |
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| 90 | samples = (int16_t *)frame->data[0]; |
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| 91 | |||
| 92 | init_get_bits8(&gb, buf, FRAME_SIZE); |
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| 93 | |||
| 94 | for (i = 0; i < LPC_ORDER; i++) |
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| 95 | lpc_refl[i] = ff_lpc_refl_cb[i][get_bits(&gb, sizes[i])]; |
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| 96 | |||
| 97 | ff_eval_coefs(ractx->lpc_coef[0], lpc_refl); |
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| 98 | ractx->lpc_refl_rms[0] = ff_rms(lpc_refl); |
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| 99 | |||
| 100 | energy = ff_energy_tab[get_bits(&gb, 5)]; |
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| 101 | |||
| 102 | refl_rms[0] = ff_interp(ractx, block_coefs[0], 1, 1, ractx->old_energy); |
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| 103 | refl_rms[1] = ff_interp(ractx, block_coefs[1], 2, |
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| 104 | energy <= ractx->old_energy, |
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| 105 | ff_t_sqrt(energy*ractx->old_energy) >> 12); |
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| 106 | refl_rms[2] = ff_interp(ractx, block_coefs[2], 3, 0, energy); |
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| 107 | refl_rms[3] = ff_rescale_rms(ractx->lpc_refl_rms[0], energy); |
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| 108 | |||
| 109 | ff_int_to_int16(block_coefs[3], ractx->lpc_coef[0]); |
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| 110 | |||
| 111 | for (i=0; i < NBLOCKS; i++) { |
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| 112 | do_output_subblock(ractx, block_coefs[i], refl_rms[i], &gb); |
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| 113 | |||
| 114 | for (j=0; j < BLOCKSIZE; j++) |
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| 115 | *samples++ = av_clip_int16(ractx->curr_sblock[j + 10] << 2); |
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| 116 | } |
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| 117 | |||
| 118 | ractx->old_energy = energy; |
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| 119 | ractx->lpc_refl_rms[1] = ractx->lpc_refl_rms[0]; |
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| 120 | |||
| 121 | FFSWAP(unsigned int *, ractx->lpc_coef[0], ractx->lpc_coef[1]); |
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| 122 | |||
| 123 | *got_frame_ptr = 1; |
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| 124 | |||
| 125 | return FRAME_SIZE; |
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| 126 | } |
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| 127 | |||
| 128 | AVCodec ff_ra_144_decoder = { |
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| 129 | .name = "real_144", |
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| 130 | .long_name = NULL_IF_CONFIG_SMALL("RealAudio 1.0 (14.4K)"), |
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| 131 | .type = AVMEDIA_TYPE_AUDIO, |
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| 132 | .id = AV_CODEC_ID_RA_144, |
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| 133 | .priv_data_size = sizeof(RA144Context), |
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| 134 | .init = ra144_decode_init, |
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| 135 | .decode = ra144_decode_frame, |
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| 136 | .capabilities = CODEC_CAP_DR1, |
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| 137 | }; |